• 제목/요약/키워드: ADHESION

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견인능력 향상을 위한 추정점착력을 이용한 점착제어기법에 관한 연구 (A Study on the Adhesion Control using the Estimated Adhesion for Improving Traction Performance)

  • 서광덕
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제48권12호
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    • pp.709-714
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    • 1999
  • This paper is focused on the adhesion control method to improve traction efficiency using the estimated adhesion for railway propulsion system. Recently, the wheel slippery is frequently occurred due to light weight of train and power increasement of traction parts. This phenomenon occurs a traction loss and a poor ride comport. Therefore, the adhesion control which is able to prevent the slippery and to control the traction on a maximum adhesion is absolutely needed. This paper introduces typical methods for adhesion control and proposes two novel adhesion methods using the estimated adhesion.

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세포흡착 거동의 기계적/생화학적 분석 (Mechanical/Biochemical Analysis of Cell Adhesion Strengthening)

  • 신흥수
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1455-1457
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    • 2008
  • Cell adhesion is a coordinated process involving initial binding of integrin receptors to extracellular matrix (ECM), recruitment of adhesion proteins, and focal adhesion assembly. The formation of mechanically stable focal adhesion assembly of cells within surrounding ECM is a key parameter to direct numerous cellular functions including cell migration, differentiation, and apotosis. With current cell adhesion assays, it is difficult to understand contributions of each coordinated event on evolution of cell adhesion strengthening since cells spontaneously spread upon their adhesion to the substrate, thus remodeling their cytoskeletal structure. In this presentation, novel approaches for analysis of cell adhesion strengthening process based on the combination of mechanical device, micro-patterned substrates, and molecular biological techniques will be discussed.

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Adhesion of clay to metal surface; Normal and tangential measurement

  • Basmenj, Amir Khabbazi;Ghafoori, Mohammad;Cheshomi, Akbar;Azandariani, Younes Karami
    • Geomechanics and Engineering
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    • 제10권2호
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    • pp.125-135
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    • 2016
  • Adhesion in geotechnical engineering is the interaction between cohesive soil and a solid surface which can cause clogging in mechanized tunnelling through clayey formations. Normal piston pull out and modified direct shear tests were performed on clayey soil samples to determine which type of adhesion stress, normal or tangential, could be most effectively measured. Measured values for normal adhesion ranged from 0.9 to 18 kPa. The range of tangential adhesion was 2.4 to 10 kPa. The results indicate normal adhesion results were more accurate than those for the modified direct shear test that measure tangential adhesion. Direct shear test on identical samples did not show any correlation between measured cohesion and normal adhesion values. Normal adhesion values have shown significantly meaningful variation with consistency index and so are compatible with the base of field clogging assessment criteria. But tangential adhesion and cohesion were not compatible with these assessment criteria.

가토의 굴곡건 손상모델에서 Mitomycin-C가 인대 유착 방지에 미치는 영향 (The Effect of Mitomycin-C on Preventing Adhesion of Injured Flexor Tendon in Rabbit Model)

  • 성정화;강소라;김양우
    • Archives of Plastic Surgery
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    • 제37권4호
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    • pp.329-334
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    • 2010
  • Purpose: Adhesion after flexor tendon injury is a result of fibrosis between tendon and tendon sheath. This, finally interfere with gliding mechanism of tendon and results in functional problem of hands. Therefore, there have been many trials to reduce adhesion around the tendon. However, there is no standard procedure clinically practiced in hospitals. Mitomycin-C is an antineoplastic alkylating agent that decrease fibroblast proliferation and scar formation. It is commonly used in many surgery to reduce postoperative adhesion. This study was designed to observe the effect of Mitomycin-C on preventing adhesion in injured flexor tendon. Methods: The deep flexor tendon of digit 2 and 4 in the left forepaw of 15 New Zealand White rabbits were subjected to partial tenotomy. In study group, injury site was exposed to a single 5-minute application of Mitomycin-C, and in control group was left untreated. Digit 2 and 4 in the right forepaw of each rabbit were considered as nonadhesion control group. After 2 weeks, the animals were sacrificed and digits were amputated for biomechanical test and histological study. Results: In biomechanical study to measure yield point, mean yield point of non-adhesion control was $17.43{\pm}2.33$ and $25.07{\pm}4.03$ for adhesion control, which proves increase of adhesion in adhesion control group (p<0.05) in 95% confidence. In Mitomycin-C group, mean yield point was $12.71{\pm}4.97$. Compared with adhesion control, there was decrease in adhesiveness in Mitomycin-C group (p<0.05) in 95% confidence. In histological study, the result of adhesion control revealed massive adhesions of bony structure, fibrotic tissue and tendon structure with ablation of the border. However in Mitomycin-C group, we could find increased fibrotic tissue, but adhesion is much lesser than adhesion group and borders between structures remain intact. Conclusion: This study suggests that Mitomycin-C can significantly reduce adhesion of injured flexor tendon in rabbit model.

Characteristics of adhesion areas between the tissue expander and capsule in implant-based breast reconstruction

  • Lim, Yoon Min;Park, Kwang Hyun;Lee, Dong Won;Lew, Dae Hyun;Roh, Tai Suk;Song, Seung Yong
    • Archives of Plastic Surgery
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    • 제46권4호
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    • pp.330-335
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    • 2019
  • Background The use of anatomic implants has improved the aesthetic results of breast surgery; however, implant malrotation is an uncommon, but serious complication of these procedures. Nevertheless, little research has explored implant adhesion. In this study, we investigated adhesion between the expander and the capsule. Methods Seventy-nine cases of immediate breast reconstruction via two-stage implant-based reconstruction performed between September 2016 and November 2017 were evaluated. Mentor CPX4 expanders were used in 14 breasts, and Natrelle expanders in 65. We analyzed areas of adhesion on the surfaces of the tissue expanders when they were exchanged with permanent implants. We investigated whether adhesions occurred on the cephalic, caudal, anterior, and/or posterior surfaces of the expanders. Results Total adhesion occurred in 18 cases, non-adhesion in 15 cases, and partial adhesion in 46 cases. Of the non-adhesion cases, 80% (n=12) were with Mentor CPX4 expanders, while 94.4% (n=17) of the total adhesion cases were with Natrelle expanders. Of the partial adhesion cases, 90.7% involved the anterior-cephalic surface. The type of tissue expander showed a statistically significant relationship with the number of attachments in both univariate and multivariate logistic regression analyses (P<0.001) and with total drainage only in the univariate analysis (P=0.015). Conclusions We sought to identify the location(s) of adhesion after tissue expander insertion. The texture of the implant was a significant predictor of the success of adhesion, and partial adhesion was common. The anterior-cephalic surface showed the highest adhesion rate. Nevertheless, partial adhesion suffices to prevent unwanted rotation of the expander.

철도차량의 제동성능 향상을 위한 점착현상에 관한 연구 (Wheel/Rail Adhesion for Improvement of Braking Performance)

  • 전규찬;황동환;김대은
    • Tribology and Lubricants
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    • 제13권2호
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    • pp.68-73
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    • 1997
  • The adhesion between wheel and rail plays an important role in the braking performance of trains. Though there have been numerous studies on the characteristics of adhesion phenomenon, a general understanding from the physical point of view is still lacking. In this work, the adhesion mechanism between wheel and rail was investigated by studying the mechanisms of pure rolling and sliding experiments. Tests were performed under various conditions to determine the physical phenomenon responsible for adhesion between wheel and rail. The results of this study is expected to aid in improving the braking performance of trains.

표면 거칠기가 나노 응착력에 미치는 영향에 관한 실험적 연구 (An Experimental Study on the Effect of Surface Roughness on Nanoscale Adhesion)

  • 양승호
    • Tribology and Lubricants
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    • 제21권1호
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    • pp.1-7
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    • 2005
  • Effect of Surface roughness on nanoscale adhesion was studied experimentally by using colloidal probe technique. Glass micro balls having the radius of $3.3\~17.4{\mu}m$ were glued at the end of AFM cantilevers to prepare colloidal probes. Adhesion force between the colloidal probe and Si-wafer was measured using pull-off force measuring method. Results showed that the measured adhesion forces are not the function of the radius of the glued balls because the ball surfaces are rough. It is also found that roughness parameters such as $R_a,\;R_q\;and\;R_{max}$ do not have important role on nanoscale adhesion. In order to find the effect of surface roughness on nanoscale adhesion, the bearing areas were extracted from the measured topography of glued balls. After normalizing the measured adhesion force with the bearing area, it was found that the normalized adhesion force kept constant as function of the radius of glued ball.

인터넷 콘텐츠서비스 이용약관의 불공정성 검토에 관한 연구 (A Study on the Unfairness of Adhesion Contracts for Internet Contents Service)

  • 박미혜;강이주
    • 대한가정학회지
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    • 제42권12호
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    • pp.123-140
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    • 2004
  • The purpose of this study was to explore the unfairness of adhesion contracts for internet contents service. The internet contents were classified into six types of avatar, learning, download, e-book and movie internet sites. The adhesion contracts of internet contents service were collected in 60 internet sites. The unfairness of the adhesion contract was reviewed under the adhesion contract regulation act. The major results were as follows. First, the obligation of clear statement, explanation, and delivery was not observed completely. Second, many articles of adhesion contract were unfair and they especially violated articles 7 and 9. Therefore, the standard adhesion contract system for internet content service should be enforced and self-regulation of information service providers is needed.

도시철도차량의 성능 향상을 위한 점착특성 기법에 관한 연구 (A Study on the adhesion characteristic technique for improvement performance of urban rolling stock)

  • 김영춘;전지용
    • 한국산학기술학회논문지
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    • 제7권2호
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    • pp.150-156
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    • 2006
  • 전기철도차량의 성능특성을 향상시키기 위한 효과적인 방법중의 하나는 바퀴와 레일사이의 점착성능을 향상시키는 것이다. 점착특성을 연구하기 위해서 실제 차량을 등가 모델링한 점착시스템을 제작하였다. 이 시스템은 다양한 점착 파라미터를 변화시켜 바퀴와 레일사이의 점착력을 바꿀 수 있도록 제작되었다. 이 논문은 공전속도를 제어하는 기능을 추가하여 점착성능을 향상시키는 연구이다.

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